We have seen the Pioneer Anomaly mentioned and the fact that they were spin stabilized making them a quiet platform to look at your Doppler measurements. It has been suggested that the New Horizon spacecraft on its way to Pluto might also be used to look at its Doppler measurements while in its spin stabilized cruise mode when it was on its way passed Jupiter and later on the way to Pluto.
- LRK -
----------------------------------------------------
Where is the New Horizons Spacecraft Now?
http://www.nasa.gov/mission_
[Short Flash trailer - LRK -]
-----------------
New Horizons Halfway to Pluto
1:40
-----------------
In 2006, NASA dispatched an ambassador to the planetary frontier. The New Horizons spacecraft is now halfway between Earth and Pluto, on approach for a dramatic flight past the icy planet and its moons in July 2015.
After 10 years and more than 3 billion miles, on a historic voyage that has already taken it over the storms and around the moons of Jupiter, New Horizons will shed light on new kinds of worlds we've only just discovered on the outskirts of the solar system.
Pluto gets closer by the day, and New Horizons continues into rare territory, as just the fifth probe to traverse interplanetary space so far from the Sun. And the first to travel so far, to reach a new planet for exploration.
snip
------------------------------
More information as to progress of New Horizons spacecraft.
- LRK -
------------------------------
Where Is New Horizons?
http://pluto.jhuapl.edu/
Click here to follow New Horizons as it passes each planet's orbit, starting with our own Moon.
Current Position
This image shows New Horizons' current position. The green segment of the line shows where New Horizons has traveled since launch; the red indicates the spacecraft's path toward Jupiter, Pluto and beyond. Positions of stars with magnitude 12 or brighter are shown from this perspective, which is above the Sun and "north" of Earth's orbit.
http://pluto.jhuapl.edu/
snip
Full Trajectory: Overhead View
This image shows New Horizons' current position along its full planned trajectory. The green segment of the line shows where New Horizons has traveled since launch; the red indicates the spacecraft's future path. Positions of stars with magnitude 12 or brighter are shown from this perspective, which is above the Sun and "north" of Earth's orbit.
http://pluto.jhuapl.edu/
snip
Full Trajectory - Side View
This image shows New Horizons' current position along its full planned trajectory. The green segment of the line shows where New Horizons has traveled since launch; the red indicates the spacecraft's future path. Positions of stars with magnitude 12 or brighter are shown from this perspective, which is slightly above the orbital plane of the planets.
http://pluto.jhuapl.edu/
snip
[Note: Suggest actually going to the web link above as they will all display with current date. - LRK -
------------------------------
Do you think you might be interested in being a member of a team that launches a probe to interstellar space?
Do you have 15 years to spend on it?
- LRK -
------------------------------
The PI's Perspective
http://pluto.jhuapl.edu/
The PI’s Perspective: Ten Years On
December 17, 2010
Billy Joel wrote a song, “This is the Time,” and my favorite verse from that old piece goes like this:
snip
http://pluto.jhuapl.edu/
------------------------------
When you take an airplane ride and wake up from a long sleep you might like to know where you are.
Sometimes it takes awhile to get your bearings, a look out the window or check the TV monitor.
If you are a spacecraft that has been in cruise mode and are awakened to check out your systems, one of things you want to know is just how far along your path have you gone. Do we have to consider something like the Pioneer Anomaly?
http://pluto.jhuapl.edu/
- LRK -
------------------------------
A New Horizons Wake Up Call
http://www.centauri-dreams.
The fix is to be a June 30 course correction involving a change in speed of about 1.5 kilometers per hour. The 30-second thruster burn will make New Horizon’s first course change since late 2007. Also coming up this summer are cruise observations of Jupiter, Uranus, Neptune and Pluto itself, along with four weeks of observations of the space plasma environment near the orbit of Uranus.
snip
------------------------------
Some snips from Wikipedia about the New Horizons mission.
More there is you care to check.
- LRK -
------------------------------
New Horizons
http://en.wikipedia.org/wiki/
>From Wikipedia, the free encyclopedia - 12-22-2010
New Horizons is a NASA robotic spacecraft mission currently en route to the dwarf planet Pluto. It is expected to be the first spacecraft to fly by and study Pluto and its moons, Charon, Nix, and Hydra. NASA may also approve flybys of one or more other Kuiper belt objects.
New Horizons was launched on January 19, 2006, directly into an Earth-and-solar-escape trajectory. It had an Earth-relative velocity of about 16.26 km/s (58,536 km/h; 36,373 mph) after its last engine shut down. Thus, it left Earth at the fastest launch speed ever recorded for a man-made object. New Horizons flew by Jupiter on February 28, 2007, and the orbit of Saturn on June 8, 2008; it is projected to arrive at Pluto on July 14, 2015, after which it will continue into the Kuiper belt.
snip
New Horizons is the first mission in NASA's New Frontiers mission category, larger and more expensive than Discovery missions but smaller than the Flagship Program. The cost of the mission (including spacecraft and instrument development, launch vehicle, mission operations, data analysis, and education/public outreach) is approximately $650 million over 15 years (from 2001 to 2016). An earlier proposed Pluto mission – Pluto Kuiper Express – was cancelled by NASA in 2000 for budgetary reasons. Further information relating to an overview with historical context[1] can be found at the IEEE website and gives further background and details, with more details regarding the Jupiter fly-by.[2]
The New Horizons craft was built primarily by Southwest Research Institute (SwRI) and the Johns Hopkins Applied Physics Laboratory (APL). The mission's principal investigator is Alan Stern (NASA Associate Administrator, formerly of the Southwest Research Institute).
snip
On April 7, 2006 at 10:00 UTC, the spacecraft passed the orbit of Mars, moving at roughly 21 km/s away from the Sun at a solar distance of 243 million kilometers.[16]
New Horizons made a distant flyby of the small asteroid 132524 APL (previously known by its provisional designation, 2002 JF56), at a distance of 101,867 km at 04:05 UTC on June 13, 2006. The best current estimate of the asteroid's diameter is approximately 2.3 kilometers, and the spectra obtained by New Horizons showed that APL is an S-type asteroid.
The spacecraft successfully tracked the asteroid over June 10 – June 12, 2006. This allowed the mission team to test the spacecraft's ability to track rapidly moving objects. Images were obtained through the Ralph telescope.[17]
snip
New Horizons has both spin-stabilized (cruise) and three-axis stabilized (science) modes, controlled entirely with hydrazine monopropellant. 77 kg (170 lb) of hydrazine provides a delta-v capability of over 290 m/s (649 mph) after launch. Helium is used as a pressurant, with an elastomeric diaphragm assisting expulsion. The spacecraft's on-orbit mass including fuel will be over 470 kg (1,036 lb) for a Jupiter flyby trajectory, but would have been only 445 kg (981 lb) for a direct flight to Pluto. This would have meant less fuel for later Kuiper belt operations and is caused by the launch vehicle performance limitations for a direct-to-Pluto flight.
snip
------------------------------
Well just another 5 years and we will see what we shall see.
Hmmm, 73 + 5 = 78, might still be around if I can cut down on my near misses while on my travels.
Hope New Horizon continues to perform well.
- LRK -
Thanks for looking up with me.
- LRK -
Web Site: http://lkellogg.vttoth.com/
BlogSpot: http://kelloggserialreports.
RSS link: http://kelloggserialreports.
Newsletter: https://news.altair.com/
==============================
Brag Points
http://www.uidaho.edu/
snip
University of Idaho special purpose computers are hurtling toward the edge of the solar system at speeds in excess of 43,000 mph aboard NASA’s New Horizons probe. The probe carrying the University’s Center for Advanced Microelectronics and Biomolecular Research’s (CAMBR) EDAC5 chip was launched Jan.19, 2006. The chip provides error correction of the data New Horizons is gathering on its groundbreaking mission. The ultimate objective of the mission is to gather information on the dwarf planet Pluto and the unexplored Kuiper Belt region beyond it. The probe is expected to arrive at Pluto in 2015.
http://www.nasa.gov/mission_
[Short Flash trailer - LRK -]
-----------------
New Horizons Halfway to Pluto
1:40
-----------------
In 2006, NASA dispatched an ambassador to the planetary frontier. The New Horizons spacecraft is now halfway between Earth and Pluto, on approach for a dramatic flight past the icy planet and its moons in July 2015.
After 10 years and more than 3 billion miles, on a historic voyage that has already taken it over the storms and around the moons of Jupiter, New Horizons will shed light on new kinds of worlds we've only just discovered on the outskirts of the solar system.
Pluto gets closer by the day, and New Horizons continues into rare territory, as just the fifth probe to traverse interplanetary space so far from the Sun. And the first to travel so far, to reach a new planet for exploration.
snip
------------------------------
More information as to progress of New Horizons spacecraft.
- LRK -
------------------------------
Where Is New Horizons?
http://pluto.jhuapl.edu/
Click here to follow New Horizons as it passes each planet's orbit, starting with our own Moon.
Current Position
This image shows New Horizons' current position. The green segment of the line shows where New Horizons has traveled since launch; the red indicates the spacecraft's path toward Jupiter, Pluto and beyond. Positions of stars with magnitude 12 or brighter are shown from this perspective, which is above the Sun and "north" of Earth's orbit.
http://pluto.jhuapl.edu/
snip
Full Trajectory: Overhead View
This image shows New Horizons' current position along its full planned trajectory. The green segment of the line shows where New Horizons has traveled since launch; the red indicates the spacecraft's future path. Positions of stars with magnitude 12 or brighter are shown from this perspective, which is above the Sun and "north" of Earth's orbit.
http://pluto.jhuapl.edu/
snip
Full Trajectory - Side View
This image shows New Horizons' current position along its full planned trajectory. The green segment of the line shows where New Horizons has traveled since launch; the red indicates the spacecraft's future path. Positions of stars with magnitude 12 or brighter are shown from this perspective, which is slightly above the orbital plane of the planets.
http://pluto.jhuapl.edu/
snip
[Note: Suggest actually going to the web link above as they will all display with current date. - LRK -
------------------------------
Do you think you might be interested in being a member of a team that launches a probe to interstellar space?
Do you have 15 years to spend on it?
- LRK -
------------------------------
The PI's Perspective
http://pluto.jhuapl.edu/
The PI’s Perspective: Ten Years On
December 17, 2010
Billy Joel wrote a song, “This is the Time,” and my favorite verse from that old piece goes like this:
“This is the time to remember
'Cause it will not last forever
These are the days to hold on to
'Cause we won't although we'll want to . . .”
Well, 10 years ago, on Dec. 19, 2000, NASA announced that it would conduct a competition for a PI-led mission to Pluto and the Kuiper Belt. At the time, I’d been involved in leading NASA’s science working group for just such a mission, and I had led a successful proposal to build a complete suite of science instruments for the mission. So, almost immediately upon NASA’s announcement, colleagues asked me to lead a Pluto-Kuiper Belt mission proposal.
Within a week of NASA’s announcement, my team had joined up with the Johns Hopkins University Applied Physics Laboratory and formed a larger mission team, which ultimately became known as New Horizons. The 11 months that our team spent together writing and then winning that proposal, and the four subsequent whirlwind years we spent building and launching New Horizons, have become days to remember.
As we enter the 2010 holiday season, with the spacecraft and instrument payload that our team built now approaching the orbit of Uranus, I can’t help but think: 10 years. Ten. Wow.
When you get involved in a project of such length — we still have more than 4 ½ years to go to get to Pluto, and another nine months after that to get all our data back on Earth — you can’t help but feel your project team is a kind of family, one you’re journeying through both space and time with.
'Cause it will not last forever
These are the days to hold on to
'Cause we won't although we'll want to . . .”
Well, 10 years ago, on Dec. 19, 2000, NASA announced that it would conduct a competition for a PI-led mission to Pluto and the Kuiper Belt. At the time, I’d been involved in leading NASA’s science working group for just such a mission, and I had led a successful proposal to build a complete suite of science instruments for the mission. So, almost immediately upon NASA’s announcement, colleagues asked me to lead a Pluto-Kuiper Belt mission proposal.
Within a week of NASA’s announcement, my team had joined up with the Johns Hopkins University Applied Physics Laboratory and formed a larger mission team, which ultimately became known as New Horizons. The 11 months that our team spent together writing and then winning that proposal, and the four subsequent whirlwind years we spent building and launching New Horizons, have become days to remember.
As we enter the 2010 holiday season, with the spacecraft and instrument payload that our team built now approaching the orbit of Uranus, I can’t help but think: 10 years. Ten. Wow.
When you get involved in a project of such length — we still have more than 4 ½ years to go to get to Pluto, and another nine months after that to get all our data back on Earth — you can’t help but feel your project team is a kind of family, one you’re journeying through both space and time with.
snip
http://pluto.jhuapl.edu/
------------------------------
When you take an airplane ride and wake up from a long sleep you might like to know where you are.
Sometimes it takes awhile to get your bearings, a look out the window or check the TV monitor.
If you are a spacecraft that has been in cruise mode and are awakened to check out your systems, one of things you want to know is just how far along your path have you gone. Do we have to consider something like the Pioneer Anomaly?
http://pluto.jhuapl.edu/
- LRK -
------------------------------
A New Horizons Wake Up Call
http://www.centauri-dreams.
by Paul Gilster on May 24, 2010
Recently we’ve been talking about long-distance repair, and how any probe launched beyond the Solar System is going to have to fix its own problems rather than relying solely on transmissions from Earth. New Horizons, halfway to Pluto/Charon in terms of distance, isn’t yet in that category. It’s going to eventually make its way into the Kuiper Belt, but for now, it’s close enough for controllers to wake it up periodically for checks. In fact, the next wakeup call, which comes tomorrow, begins a nine-week period of rigorous tests.
Long-term missions like New Horizon demand annual checkouts, and this one (as opposed to last year’s) is to be comprehensive, ranging from conducting heliospheric cruise science to uploading a series of code enhancements and bug fixes to the spacecraft’s fault protection software. The spacecraft’s backup systems will be checked and its seven scientific instruments re-calibrated. Principal investigator Alan Stern describes the process in his latest report.
http://pluto.jhuapl.edu/
snip
Not all fixes to a spacecraft involve repairing malfunctioning systems. In the case of New Horizons, it’s also necessary to keep a close eye on the course. With the vehicle well into the outer Solar System, it’s interesting to speculate about what forces could be causing the need for a course correction. No, it’s not the so-called ‘Pioneer Anomaly,’ but the reflection of thermal photons from New Horizons’ radioisotope thermoelectric generator (RTG) striking the back of its high-gain antenna. A tiny effect multiplied over four years has consequences. Recently we’ve been talking about long-distance repair, and how any probe launched beyond the Solar System is going to have to fix its own problems rather than relying solely on transmissions from Earth. New Horizons, halfway to Pluto/Charon in terms of distance, isn’t yet in that category. It’s going to eventually make its way into the Kuiper Belt, but for now, it’s close enough for controllers to wake it up periodically for checks. In fact, the next wakeup call, which comes tomorrow, begins a nine-week period of rigorous tests.
Long-term missions like New Horizon demand annual checkouts, and this one (as opposed to last year’s) is to be comprehensive, ranging from conducting heliospheric cruise science to uploading a series of code enhancements and bug fixes to the spacecraft’s fault protection software. The spacecraft’s backup systems will be checked and its seven scientific instruments re-calibrated. Principal investigator Alan Stern describes the process in his latest report.
http://pluto.jhuapl.edu/
snip
The fix is to be a June 30 course correction involving a change in speed of about 1.5 kilometers per hour. The 30-second thruster burn will make New Horizon’s first course change since late 2007. Also coming up this summer are cruise observations of Jupiter, Uranus, Neptune and Pluto itself, along with four weeks of observations of the space plasma environment near the orbit of Uranus.
snip
------------------------------
Some snips from Wikipedia about the New Horizons mission.
More there is you care to check.
- LRK -
------------------------------
New Horizons
http://en.wikipedia.org/wiki/
>From Wikipedia, the free encyclopedia - 12-22-2010
New Horizons is a NASA robotic spacecraft mission currently en route to the dwarf planet Pluto. It is expected to be the first spacecraft to fly by and study Pluto and its moons, Charon, Nix, and Hydra. NASA may also approve flybys of one or more other Kuiper belt objects.
New Horizons was launched on January 19, 2006, directly into an Earth-and-solar-escape trajectory. It had an Earth-relative velocity of about 16.26 km/s (58,536 km/h; 36,373 mph) after its last engine shut down. Thus, it left Earth at the fastest launch speed ever recorded for a man-made object. New Horizons flew by Jupiter on February 28, 2007, and the orbit of Saturn on June 8, 2008; it is projected to arrive at Pluto on July 14, 2015, after which it will continue into the Kuiper belt.
snip
New Horizons is the first mission in NASA's New Frontiers mission category, larger and more expensive than Discovery missions but smaller than the Flagship Program. The cost of the mission (including spacecraft and instrument development, launch vehicle, mission operations, data analysis, and education/public outreach) is approximately $650 million over 15 years (from 2001 to 2016). An earlier proposed Pluto mission – Pluto Kuiper Express – was cancelled by NASA in 2000 for budgetary reasons. Further information relating to an overview with historical context[1] can be found at the IEEE website and gives further background and details, with more details regarding the Jupiter fly-by.[2]
The New Horizons craft was built primarily by Southwest Research Institute (SwRI) and the Johns Hopkins Applied Physics Laboratory (APL). The mission's principal investigator is Alan Stern (NASA Associate Administrator, formerly of the Southwest Research Institute).
snip
On April 7, 2006 at 10:00 UTC, the spacecraft passed the orbit of Mars, moving at roughly 21 km/s away from the Sun at a solar distance of 243 million kilometers.[16]
New Horizons made a distant flyby of the small asteroid 132524 APL (previously known by its provisional designation, 2002 JF56), at a distance of 101,867 km at 04:05 UTC on June 13, 2006. The best current estimate of the asteroid's diameter is approximately 2.3 kilometers, and the spectra obtained by New Horizons showed that APL is an S-type asteroid.
The spacecraft successfully tracked the asteroid over June 10 – June 12, 2006. This allowed the mission team to test the spacecraft's ability to track rapidly moving objects. Images were obtained through the Ralph telescope.[17]
snip
New Horizons has both spin-stabilized (cruise) and three-axis stabilized (science) modes, controlled entirely with hydrazine monopropellant. 77 kg (170 lb) of hydrazine provides a delta-v capability of over 290 m/s (649 mph) after launch. Helium is used as a pressurant, with an elastomeric diaphragm assisting expulsion. The spacecraft's on-orbit mass including fuel will be over 470 kg (1,036 lb) for a Jupiter flyby trajectory, but would have been only 445 kg (981 lb) for a direct flight to Pluto. This would have meant less fuel for later Kuiper belt operations and is caused by the launch vehicle performance limitations for a direct-to-Pluto flight.
snip
------------------------------
Well just another 5 years and we will see what we shall see.
Hmmm, 73 + 5 = 78, might still be around if I can cut down on my near misses while on my travels.
Hope New Horizon continues to perform well.
- LRK -
Thanks for looking up with me.
- LRK -
Web Site: http://lkellogg.vttoth.com/
BlogSpot: http://kelloggserialreports.
RSS link: http://kelloggserialreports.
Newsletter: https://news.altair.com/
==============================
Brag Points
http://www.uidaho.edu/
snip
University of Idaho special purpose computers are hurtling toward the edge of the solar system at speeds in excess of 43,000 mph aboard NASA’s New Horizons probe. The probe carrying the University’s Center for Advanced Microelectronics and Biomolecular Research’s (CAMBR) EDAC5 chip was launched Jan.19, 2006. The chip provides error correction of the data New Horizons is gathering on its groundbreaking mission. The ultimate objective of the mission is to gather information on the dwarf planet Pluto and the unexplored Kuiper Belt region beyond it. The probe is expected to arrive at Pluto in 2015.
snip
==============================
MIT Clug of Ottawa
http://mitottawa.ncf.ca/
Meetings from 2005-2006 Season
snip
7 February, 2006
The Pioneer Anomaly -
Seeking an explanation in on-board telemetry
Viktor Toth Pioneer 10 and 11, launched over three decades ago, remain the most precisely navigated deep space craft to date. They are true "pioneers" in many respects: they were the first to venture beyond the orbit of Mars, first to cross the asteroid belt, first to fly by Jupiter and Saturn, and first to leave the Solar System. They functioned far beyond their design lifetime: Pioneer 10 sent its last telemetry in 2002, 30 years after it departed the Earth, from a distance three times that of Pluto. However, if viewed as a test of general relativity, the Pioneers failed to confirm Einstein's predictions: after accounting for known forces, a small, anomalous acceleration remains, slowing down the spacecraft ever so slightly. There have been many attempts to account for this anomaly using both known and new physics. A recent effort to recover the entire mission record of the Pioneers made a new approach possible: the use of telemetry to analyze the contribution of forces of on-board origin to the Pioneers' motion.
Viktor Toth (http://www.vttoth.com/) is a software developer and author of computer books. Several years ago, he began to collaborate with Larry Kellogg from NASA's Ames Research Center in an effort to preserve the 30 year telemetry record of both Pioneers. With the code Viktor developed, it became possible to read these data files on modern computers. A draft of a report on the current status of this work, accepted for publication by the International Journal of Modern Physics D, can be read in preprint form at http://arxiv.org/abs/gr-qc/
snip
==============================
The Quest to Understand the Pioneer Anomaly
http://arxiv.org/ftp/gr-qc/
LA-UR-06-6181
Michael Martin Nieto
Theoretical Division (MS-B285)
Los Alamos National Laboratory
Los Alamos, New Mexico 87545 U.S.A
Summary: The Pioneer 10/11 missions, launched in 1972 and 1973, and their navigation are
reviewed. Beginning in about 1980 an unmodeled force of ~ 8 x 10-8 cm/s2 appeared in the
tracking data, it later being verified. The cause remains unknown, although radiant heat remains
a likely origin. A set of efforts to find the solution are underway: a) analyzing in detail all
available data, b) using data from the New Horizons mission, and c) considering an ESA
dedicated mission.
snip
b) The New Horizons mission to Pluto
On 19 Jan 2006 the New Horizons mission to Pluto and the Kuiper Belt was launched from Cape
Canaveral. Although it was not designed for precision tracking, it might be able to yield useful
information.
snip
A saving grace may be that soon after launch a 180 degree “Earth acquisition manoeuvre”
rotation was performed, to aim the main antenna at the Earth. The difference in the Doppler shift
immediately before and after the rotation can in principle yield a difference measurement of the
heat acceleration which would be pointed first in one direction and then in the opposite. But a
determination may be difficult because of the high solar radiation pressure (which will vary
somewhat in the two orientations) and the relatively small data set before the manoeuvre.
More gratifyingly, New Horizons will be in spin-stabilization mode for about the six months
before the Jupiter observing period (January-June, 2007, with encounter on 28 Feb. 2007). It
also will be spin-stabilized for much of the period after June 2007 until soon before the Pluto
encounter on 14 July 2015. This is designed to save fuel so it can be used to aim later at a
Kuiper Belt Object. With luck the Doppler and range data from these periods will supply a test,
at some level, of the Pioneer anomaly, especially since the velocity of the craft before (~21 km/s)
and after (~25 km/s) the Jupiter encounter will be significantly different that those of the
Pioneers (~12 km/s). Perhaps something can be learned from the New Horizons data by 2008.
snip
==============================
WHAT THE MIND CAN CONCEIVE, AND BELIEVE, IT WILL ACHIEVE - LRK
==============================
==============================
MIT Clug of Ottawa
http://mitottawa.ncf.ca/
Meetings from 2005-2006 Season
snip
7 February, 2006
The Pioneer Anomaly -
Seeking an explanation in on-board telemetry
Viktor Toth Pioneer 10 and 11, launched over three decades ago, remain the most precisely navigated deep space craft to date. They are true "pioneers" in many respects: they were the first to venture beyond the orbit of Mars, first to cross the asteroid belt, first to fly by Jupiter and Saturn, and first to leave the Solar System. They functioned far beyond their design lifetime: Pioneer 10 sent its last telemetry in 2002, 30 years after it departed the Earth, from a distance three times that of Pluto. However, if viewed as a test of general relativity, the Pioneers failed to confirm Einstein's predictions: after accounting for known forces, a small, anomalous acceleration remains, slowing down the spacecraft ever so slightly. There have been many attempts to account for this anomaly using both known and new physics. A recent effort to recover the entire mission record of the Pioneers made a new approach possible: the use of telemetry to analyze the contribution of forces of on-board origin to the Pioneers' motion.
Viktor Toth (http://www.vttoth.com/) is a software developer and author of computer books. Several years ago, he began to collaborate with Larry Kellogg from NASA's Ames Research Center in an effort to preserve the 30 year telemetry record of both Pioneers. With the code Viktor developed, it became possible to read these data files on modern computers. A draft of a report on the current status of this work, accepted for publication by the International Journal of Modern Physics D, can be read in preprint form at http://arxiv.org/abs/gr-qc/
snip
==============================
The Quest to Understand the Pioneer Anomaly
http://arxiv.org/ftp/gr-qc/
LA-UR-06-6181
Michael Martin Nieto
Theoretical Division (MS-B285)
Los Alamos National Laboratory
Los Alamos, New Mexico 87545 U.S.A
Summary: The Pioneer 10/11 missions, launched in 1972 and 1973, and their navigation are
reviewed. Beginning in about 1980 an unmodeled force of ~ 8 x 10-8 cm/s2 appeared in the
tracking data, it later being verified. The cause remains unknown, although radiant heat remains
a likely origin. A set of efforts to find the solution are underway: a) analyzing in detail all
available data, b) using data from the New Horizons mission, and c) considering an ESA
dedicated mission.
snip
b) The New Horizons mission to Pluto
On 19 Jan 2006 the New Horizons mission to Pluto and the Kuiper Belt was launched from Cape
Canaveral. Although it was not designed for precision tracking, it might be able to yield useful
information.
snip
A saving grace may be that soon after launch a 180 degree “Earth acquisition manoeuvre”
rotation was performed, to aim the main antenna at the Earth. The difference in the Doppler shift
immediately before and after the rotation can in principle yield a difference measurement of the
heat acceleration which would be pointed first in one direction and then in the opposite. But a
determination may be difficult because of the high solar radiation pressure (which will vary
somewhat in the two orientations) and the relatively small data set before the manoeuvre.
More gratifyingly, New Horizons will be in spin-stabilization mode for about the six months
before the Jupiter observing period (January-June, 2007, with encounter on 28 Feb. 2007). It
also will be spin-stabilized for much of the period after June 2007 until soon before the Pluto
encounter on 14 July 2015. This is designed to save fuel so it can be used to aim later at a
Kuiper Belt Object. With luck the Doppler and range data from these periods will supply a test,
at some level, of the Pioneer anomaly, especially since the velocity of the craft before (~21 km/s)
and after (~25 km/s) the Jupiter encounter will be significantly different that those of the
Pioneers (~12 km/s). Perhaps something can be learned from the New Horizons data by 2008.
snip
==============================
WHAT THE MIND CAN CONCEIVE, AND BELIEVE, IT WILL ACHIEVE - LRK
==============================
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